Automotive instrument clusters have lenses which typically are injection molded from a plastic material and have a thickness of 2.5 to 3 mm. Most lenses are attached to retainers by screws and/or snap fasteners, although some newer designs employ ultrasonic welding of the molded lenses to their retainers to lower costs and to eliminate squeaks and rattles. There are numerous quality issues with designs using molded lenses, the molding operation being the prime contributor of problems. Optical inclusions (black and white specks), scratches, splay, suction cup marks and post molded dirt attraction make up the majority of the quality problems.